Ulloa in his voyage, and Buffon on the authority of old writers, relate a fact which illustrates very clearly the principle before explained by us, of the check which the increase of one animal necessarily offers to that of another.

He therefore left Francis de Ulloa with the command of his ships, ordering him to proceed on discoveries; and going to Acapulco, he received a messenger from Don Antonio de Mendoça, the new viceroy, certifying his arrival, and the assumption of his authority.